Aging Clinical and Experimental Research
Physical performance across the thyroid function values
within the normal range in adult and older persons
· Michela Marina
· Fulvio Lauretani
· Marcello Maggio
· Maria Francesca Serra
· Stefania Bandinelli
· Gian Paolo Ceda
· Luigi Ferrucci
Received: 5 March 2018 / Accepted: 22 May 2018
© Springer International Publishing AG, part of Springer Nature 2018
Background Thyroid hormone variation may be correlated with adverse health outcomes, even within the normal reference
range in euthyroid individuals.
Aims To determine the association between plasma thyroid-stimulating hormone (TSH), free triiodothyronine (FT3), and
free thyroxine (FT4) levels and physical performance score in middle age and older adults who had levels of all three hor-
mones in the normal range.
Methods In this community-based, cross-sectional study, euthyroid participants of the Invecchiare in Chianti study, aged
23–102 years (N = 1060), were considered. Physical performance was evaluated by the Summary Physical Performance
Battery (SPPB) score. Plasma TSH, FT3, and FT4 levels were predictors, and SPPB score was the outcome.
Results At the univariate analyses, TSH, FT4, and FT3 were not signiﬁcantly associated with SPPB score in young individu-
als, whereas, in older participants, SBBP score was positively (P < 0.001) associated with FT3, and negatively associated with
both TSH (P < 0.02) and FT4 (P < 0.001). After adjusting for multiple confounders, FT3 remained signiﬁcantly associated
with SPPB (beta ± SE, 0.35 ± 0.17, P = 0.04), but FT4 and TSH were not. Results did not change when all the three hormones
FT3, FT4, and TSH were simultaneously considered in the fully adjusted model (beta ± SE for FT3, 0.37 ± 0.18, P = 0.04).
Discussion The results of this study demonstrate that SPPB score is positively associated with circulating FT3 but not with
FT4 or with TSH, in older euthyroid individuals.
Conclusions In euthyroid older adults, circulating FT3 may play an important role in the thyroid eﬀects on physical function.
Keywords Thyroid · Free triiodothyronine · Elderly · Mobility
Functional autonomy requires the integrity of many anatom-
ical and physiological systems, including both central and
peripheral nervous system and muscle. Normal thyroid func-
tion is important for maintaining the integrity of anatomi-
cal and physiological factors essential to mobility, including
muscle structure as well as the central nervous system [1, 2].
A relatively recent literature demonstrated that thyroid
hormone variation may be correlated with adverse health
outcomes, even within the normal reference range in euthy-
TSH circulating concentration within the reference range
but close to the lower limit of normal levels have been
reported to be associated with risk of hip fracture in euthy-
roid women aged 65 and older . Higher FT4 circulating
concentrations within the normal reference range have been
Electronic supplementary material The online version of this
article (https ://doi.org/10.1007/s4052 0-018-0975-0) contains
supplementary material, which is available to authorized users.
* Graziano Ceresini
Department of Medicine and Surgery, Endocrinology
of Aging Unit, University Hospital of Parma, Via Gramsci,
14-43126 Parma, Italy
Critical Care Unit, University of Parma, Parma, Italy
Geriatric Unit, ASF Toscana, Florence, Italy
National Institute on Aging, Baltimore, MD, USA